Someone here really good with bearings?

Hukshawn said:
I'm fairly sure... But now I'm not so sure any more since you question.

The pulley bearing was a 207. I recieved those today. I'll put them in tonight.
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On a true Bridgeport, the lower bearings started out as 7207's, later changed to 2MM207xxx. The upper bearing was a 6206 or just a plain 206 bearing with shields. The pulley bearings were like a 6008 or something like that. It's been a while.
206 bearings will work for the spindle lower, just means a lightweight spindle in you mill. It's all supported by bearings, so it shouldn't make that big of difference in performance.

I'm sorry, I'm being too critical over your mill. It's the engineer in me, sorry. Ken
 
Not at all! The more info I can get, the better. I contacted First, they had absolutely nothing to offer as far as info/manuals/documents.
I'm about to head to the garage, I'll recheck the bearings.
 
Nachi (Japan) makes great moderately priced bearings, you could just put another set of those 6206s in and probably get several years of fun
out of it- put the savings toward tools and other goodies!
I'm sold on Nachi. I get them from JSB Great bearings on Ebay- fast shipping, good prices.
I have used a Chinese bearing brand called HCH, they seem fine for less critical applications. Cheaper. One of the leading Chinese brands I'm told.
Mark S.
 
mikey said:
The 7206 has exactly the same dimensions as your 6206 bearings so they are a direct replacement. Just search for the best deal you can find on the 7206-B-2RS-TVP bearings. This FAG bearing is a class P5 bearing and should suffice. You can find more info here: http://medias.schaeffler.com/medias/en!hp.ec.br.pr/72..-B-2RS*7206-B-XL-2RS-TVP. Be sure to click on the tabs to sort out what the different letters in the bearing designation mean.

I also discussed them and their installation here: http://www.hobby-machinist.com/threads/spindle-bearing-replacement-for-the-rf-31-mill-drill.49002/
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Just a quick note for you mikey. The 6206 is a deep groove ball bearing indented to take radial load only. The 7206 although having the same envelope dimensions (OD, ID, and Width) is a ball thrust bearing. They are intended for different applications.
 
HRgx said:
Just a quick note for you mikey. The 6206 is a deep groove ball bearing indented to take radial load only. The 7206 although having the same envelope dimensions (OD, ID, and Width) is a ball thrust bearing. They are intended for different applications.
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The 7206- B-2RS-TVP bearing I listed is a FAG angular contact bearing.
 
mikey said:
The 7206- B-2RS-TVP bearing I listed is a FAG angular contact bearing.
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Right mikey, an angular ball thrust bearing or "thrust" bearing - same thing. Sometimes the 72xx series bearings can be installed as pairs in a back to back or face to face or tandem (face to back) configuration. The situation in which they are installed is determined by either the amount of thrust load to be taken up, or whether there is active or inactive thrust load. In a lathe, it should not matter as the load will likely be inwards towards the chuck. In summarizing although both a 6206 and a 7206 have the same envelope dimensions, being OD, ID and WIDTH, they are intended for a different purpose. In some cases, a 6206 and 7206 will be fitted on the same shaft. The 6206 takes up heavy radial load and the 7206 takes up thrust load.
 
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Hukshawn said:
Sooooo, I goofed.
Refer here

http://www.hobby-machinist.com/threads/b-port-clone-rebuild.62975/page-2#post-522350
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No you didn't goof buddy, you are simply looking for help is how I take it. You asked for bearing experts. I am one of those guys have worked on jet engine turbines that spin at 16,000 RPM or old school integral gas compressors that spin at a mere 400 RPM. I know more about bearings than those guys that you call on the phone at the bearing supplier shop, all the they want is your PO# and the address to which to ship it. I deal with precision fits. Such as the internal clearances with which to set the likes of of double row spherical bearings on high speed machinery. Most millwrights that I've encountered rely upon "rules of thumbs". Sorry, that don't cut it for me, as when I push the button on a gas fired turbine that ramps up to 16,000 RPM, my rear end ain't gonna pucker up. No way, when the button is pushed, I'm totally relaxed. Why?, because I've documented every step of he overhaul. That my friend is absolute confidence in your work. And if you can't have such confidence, then one ought to pick another destination.
 
Not sure where that was going. Lol.

I hadn't taken the spindle out yet. I was reading the bearing number off the top shaft bearing that I could see and assumed it was the actual spindle bearings. But there's actually 3 bearings. One smaller and two larger spindle bearings. I read and ordered the smaller bearing on top. Which lucked out cause turns out that was the crunchy bearing. So frankly, all this for nothing. Lol. But I did learn a bit about bearings. As I knew nothing previously.
 
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